Weft yarn mixing device for shuttleless looms

ABSTRACT

In a shuttleless weaving loom wherein the weft yarn transfer is effected according to the so-called &#39;&#39;&#39;&#39;Gabler&#39;&#39;&#39;&#39; system, a device for mixing two weft yarns under the control of a pair of cams acting upon respective yarn guides through the medium of a lever pivotally connected to a pair of adjustable links, one pivoted to an arm above the pivot axis thereof, the other to another arm but beneath the pivot axis thereof, one arm being movable from its operative position to its inoperative position, and vice versa, a positioning bent fork controlled by another cam being provided for engaging the weft yarn moving past said fork and to lower same to an operative position in which it can be picked up by an insertion member, with a very smooth movement precluding any damage to the yarns.

United States Patent 1191 Remond 1 Aug. 28, 1973 [54] W YARN XI DEVICE FOR Primary Examiner-Henry S. Jaudon SHUmELESS LOOMS Attorney-Eric H. Waters et a1.

[75] Inventor: Pierre Remond, Bourgoin-Jallieu,

France a [57] ABSTRACT [73] Assignee: Atellerl Dlederlchs,

gourgoimjameu' France In a shuttleless weaving loom wherem the weft yarn transfer is effected according to the so-called Gabler" Filed! 1971 system, a device for mixing two weft yarns under the [21] Appl No; 199,630 control of a pair of cams acting upon respective yarn v guides through the medium of a lever pivotally connected to a pair of adjustable links, one pivoted to an [30] 9 Apphcatlon Priority Data arm above the pivot axis thereof, the other to another Dec. 21, 1970 France ..7047l57 am but beneath the pivot axis thereof, one am being 52 Us. (:1. 139/122 w, 139/127 R mwable from Operative its imperative [51 m. 01 003a 47/38 w and vice a Positioning fork 581 Field of Search 139/122 R, 122 w, "(med by amber cam being Pwvided engaging the 139/126, 127 R 127 P weft yam moving past said fork and to lower same to an operative position in which it can be picked up by [56] Reference, Cmd an insertion member, with a very smooth movement UNITED STATES PATENTS precluding any damage to the yarns.

1,964,692 6/1934 Benjamin 139/122 W 2,749,946 6/1956 Pfarrwaller 139/126 3,610,295 10/1971 Haltmeier 139/122 W 3 Claims, 13 Drawing Figures FOREIGN PATENTS 0R APPLICATIONS 1,299,032 6/1962 France 139/122 W PATENTED-MIG28 um SHEET 2 BF 4 PATENTEUAUGZB I975 SHEET Q [If 4 WEFT YARN MIXING DEVICE FOR SIIUTTLELESS LOOMS The present invention relates to weft yarn mixing de vices of the type equipping certain shuttleless weaving looms.

It is the essential object of this invention to provide a device considerably simplified from the dual point of view of construction and operation, and capable of .mixing weft yarns without selection in the pick-to-pick fashion.

In this device each one of the two yarns is directed through a yarn guide located at one end of a movable arm adapted to pivot about a fixed axis but normally held in an inoperative position, i.e. outside the path of a member adapted to move the weft yam to a position such that it can be picked up and then carried along into the shed by aninsertion member.

These yarn guides are controlled by a cam rotatably driven from a shaft rotating in synchronism with the weaving loom. This cam is adapted to control the oscillation of a lever pivotally connected to a pair of links, one link being pivoted to an arm, above the pivot axis thereof, and other link to another arm beneath the same pivot axis, one arm being movable from its operative position to its inoperative position, and vice versa.

According to another object of this invention a positioning fork controlled by another cam is adapted to engage the weft yarn, moving past said fork and to move same to an operative position in which it can be picked up by the insertion member.

The weft yarn is moved to its operative position by said fork during the insertion cycle of the preceding pick, so that particularly smooth movements can. be produced which avoid any damage to the yarn.

A clearer understanding of this invention will be had as the following description proceeds with reference to the attached drawing illustrating schematically by way of example a typical form of embodiment of this device in the specific case of its application to a loomwherein the weft yarn transfer is carried out according to the socalled Gabler system. In the drawing FIG. 1 is a general schematic front elevational view of the inventive weft yarn mixing device, showing the position normally occupied by the device in the loom FIG.2 is a partly sectional plan view of the mixing device, the section being taken through the axes of the various control mechanisms FIGS. 3 and 4 are similar to FIG. I but limited to the means controlling the arms supporting the weft yarn guide eyelets, in their respective two positions;

FIGS. 5 and 6 are views similar to that of FIG. 1 but comprising only the means controlling the pivoting fork for the insertion of the weft yarn in the operating and idle positions of the fork, respectively;

FIG. 7 is a detailed sectional view showing the mounting of the pair of control. cams;

FIG. 8 is a perspective view of a notched working part ensuring the positioning of the inserted yarn;

FIG. 9 is an'elevational view showing the diagram of the area in which the weft insertion member is operative and FIGS. 10, I1, 12 and 13 are diagrams showing in plan view from above the various steps of the pick insertions movement.

A main support member 2 tov which the weft yarn mixing device is mounted, is adapted to be traversed very easily as a function of the cloth width along a bar I disposed across the looin. This support member 2 is locked in the proper position on said-bar I by means of ascrew3.

The weft yarn selecting motion is derived from a shaft 4 rotating in synchronism with the loom and rotatably driving in turn a tubular camshaft 25 fastened to shaft 4 by means of set screws 26. This tubular camshaft is centered or journalled for free rotation in support member 2 and carries a pair of cams 5 and 45 controlling the different motions of the device.

A two-armed lever 8 (FIGS. 1 to 4) fulcrumed to a stationary pivot pin 9 carries on its lower arm a roller follower 6 rotating loosely on a pin 7. Thisroller follower is urged against cam 5 by a spring 20 attached at points 21 and 19.

The upper arm of lever 8 has pivoted thereto through a. pin I0 a pair of control links 11 and II. of the turnbuckle or adjustable length type.

A pair of arms 14 and I6 controlled by said links 11 and 11' are pivoted to a common pin I7 and comprise guide eyelets 22 and 22, respectively, constantly engaged by the pair of weft yarns to be mixed.

The oscillation of lever 8 about its pivot pin 9 in the clockwise direction is attended, through the medium of link 11 pivoted at 13 above the axis of pin 17, by the oscillation of arm 14. Thus, the weft yarn engaging the eyelet 22 is moved to its operative or pick position. At the same time the arm 16 through the medium of link 11 pivoted at 15 under the axis of pin 17 is moved from its previous selected or pick position to its inoperative position.

Conversely, when the lever 8 oscillates in the counterclockwise direction the arm 14 is moved to its inoperative position and the arm 16 recedes towards the selection point (see FIG. 1).

The contour of cam 5 is such that it produces a smooth movement avoiding any undesired harshness in the yarn treatment.

This weft yarn mixing device is completed by a fork 58 adapted to lower the selected yarn in front of the insertion member of the weaving loom. The movement of this fork 58 is controlled through a cam 45 rigid with the tubular camshaft 25, and urged thereagainst by a return spring 63 attached at 64 (FIGS. 5 and 6).

The cam 45 is adapted to cause the oscillation of a two-armed lever 50 rigid with a hub 51 mounted for free rotation on shaft 9 and having also clamped thereon an arm 49 carrying a roller follower (FIG. 2).

This two-armed lever 50 is connected through a link 54 of the turnbuckle or adjustable-length type to one arm of another two-armed lever 56 fulcrumed on a pivot pin 62 and carrying on its other arm the bent fork 58.

Underlying the bent fork 58 and at a fixed location, in close vicinity of the path of the member 66 provided for inserting the weft, is a member 65. This member (FIG. 8) has a U-contour and its two wings 70, 71 are cut slantwise to form two inclined ramps 72, 73 whose purpose is to ensure the insertion and support of the weft yarn at the instant when it is cut by a shear (FIG. 12) dipping between the two wings 70, 71.

The ramps 72, 73 each comprise a notch 74, 75, respectively. Said notches are staggered heightwise relatively to each other and their function is to assure the restraint and retention of the weft yarn so that at the instant the fork 58 drops, said yarn does not exert too heavy a pull at point where it still adjoins the selvedge of the fabric (FIGS. through 13).

The member 65 includes additionally two arms 76, 77 forming the yarn guide, between which arms the weft yarn travels. It also includes a seating 78 allowing its attachment to the loom frame and a stiffener rod 79 forming a bracing strut.

The diagrams of FIGS. 9 to 11 illustrate the path followed by the selected weft yarn when it is lowered by the bent fork 58.

This weft yarn constantly attached to the cloth selvedge at point 0, travels continuously through the eyelet of the relevant yarn guide arm. When actuated, this last-named arm transfers the weft yarn from point A to point B. During this travel (FIG. 10) the yarn slides along the ramp portion of hollow member 65. Thus, it engages the notches 74, 75 and is positioned for engagement by the fork 58 so as to be transferred thereby.

Upon completion of the downward movement of fork 58, under the control of cam 45 and return spring 63, the weft yarn is properly positioned for being inserted into the shed by the insertion member 66 by assuming an hairpin configuration until the exchange takes place in the central portion of the shed on the pick-up member 65 (FIG. 12).

After this exchange step the fork 58 is moved upwards, the yarn section 0-0 is cut by shears 80 and then carried along to the opposite selvedge of the cloth by the hook-shaped pick-up member 65 (FIG. 13), according to the well-known Glaber system.

It may'be emphasized that the contour of cam 5 is so designed that, once the weft yarn has been picked up by the insertion member and the yarn lowering fork has been raised again, the weft yarn can be moved gradually away from the insertion member to avoid any risk of damaging the yarn or causing same to be carried along during its return movement.

The device has been described and illustrated as comprising single-acting cams, but it will be readily understood that this inventioncontemplates likewise double-acting cams (such as .groovecarns or the like) permitting of dispensing with return springs.

On the other hand it is clear that this device can easily be converted for operation with a single weft yarn; in this case it is only necessary to lock one of the yarn guide arms in its inoperative position and to change the relevant control cam in order 'to impart to the other yarn guide arm a movement such that its yarn is presented for insertion at each loom cycle instead of every other cycle.

Finally, it will readily occur to those conversant with the art that this invention should not be construed as being strictly limited to the single form of embodiment described and illustrated herein, since many modifications and variations may be brought thereto without departing from the basic principles of the invention as set forth in the appended claims.

What is claimed as new is l. A device for mixing two weft yarns according to the pick-to-pick process, without selection, in a shuttleless weaving loom, comprising two independent oscillating guide members in which the yarns are constantly engaged, in combination with a member for lowering the selected yarn for positioning the same in the path of an insertion member, wherein said guide members are mounted in pendular fashion on a single common pivot pin and are controlled likewise from a single lever through a pair of links acting upon said guide members above and beneath said common pivot pin.

2. The device as defined in claim 1, further comprising means for moving said guide members away from their selective operative position and towards their inoperative position when the yam has been picked up by said insertion member, together with a pivoting fork for selectively presenting the yarns in said path of the insertion member.

3. The device as defined in claim 2, further comprising a fixed member formed with an inclined ramp and also with notch means for accurately positioning the selected yarn presented by said pivoting fork. 

1. A device for mixing two weft yarns according to the pick-topick process, without selection, in a shuttleless weaving loom, comprising two independent oscillating guide members in which the yarns are constantly engaged, in combination with a member for lowering the selected yarn for positioning the same in the path of an insertion member, wherein said guide members are mounted in pendular fashion on a single common pivot pin and are controlled likewise from a single lever through a pair of links acting upon said guide members above and beneath said common pivot pin.
 2. The device as defined in claim 1, further comprising means for moving said guide members away from their selective operative position and towards their inoperative position when the yarn has been picked up by said insertion member, together with a pivoting fork for selectively presenting the yarns in said path of the insertion member.
 3. The device as defined in claim 2, further comprising a fixed member formed with an inclined ramp and also with notch means for accurately positioning the selected yarn presenTed by said pivoting fork. 